X-Git-Url: https://gerrit.automotivelinux.org/gerrit/gitweb?a=blobdiff_plain;ds=sidebyside;f=low-can-binding%2Fcan%2Fcan-decoder.cpp;h=0e64cccd1d4617c416a00ebfb904b9466b808016;hb=0ff6413b6dc42849f87ce8caa17a91f44ede2f93;hp=566266913beb91b6dba71ca1f290ec120b821fc0;hpb=64691cf96f9c4d7ff59dbd49e1fe01d26c1a00f6;p=apps%2Fagl-service-can-low-level.git

diff --git a/low-can-binding/can/can-decoder.cpp b/low-can-binding/can/can-decoder.cpp
index 56626691..0e64cccd 100644
--- a/low-can-binding/can/can-decoder.cpp
+++ b/low-can-binding/can/can-decoder.cpp
@@ -23,6 +23,66 @@
 #include "../binding/low-can-hat.hpp"
 #include "../utils/converter.hpp"
 
+/// @brief Handle sign of the signal according to several decoding methods
+///
+/// @param[in] signal - The signal
+/// @param[in] data_signal - The data of the signal
+/// @param[in] new_end_bit - The last bit of in the last byte of the data (data_signal[0])
+/// @param[in] can_data - The whole can data (needed for SIGN BIT EXTERN)
+///
+/// @return Returns the sign of the data
+///
+int decoder_t::handle_sign(const signal_t& signal, std::vector<uint8_t>& data_signal, uint8_t new_end_bit, const std::vector<uint8_t>& can_data)
+{
+	uint8_t data_byte = 0;
+	uint8_t mask = 0;
+	int end_bit = 0;
+
+	if(signal.get_sign() == sign_t::UNSIGNED)
+		return 1;
+	else if(signal.get_sign() == sign_t::SIGN_BIT_EXTERN) {
+		end_bit = signal.get_bit_sign_position()%8;
+		mask = static_cast<uint8_t>((1 << (end_bit + 1)) - 1);
+		data_byte = can_data[signal.get_bit_sign_position()/8] & mask;
+	}
+	else {
+		end_bit = new_end_bit;
+		mask = static_cast<uint8_t>((1 << (end_bit + 1)) - 1);
+		data_byte = data_signal[0] & mask;
+	}
+
+	//if negative: decode with right method
+	if(data_byte  >> end_bit) {
+		switch(signal.get_sign())
+		{
+			//remove the sign bit to get the absolute value
+			case sign_t::SIGN_BIT:
+				data_signal[0] = static_cast<uint8_t>(data_signal[0] & (mask >> 1));
+				break;
+			//same method twos complement = ones complement + 1
+			case sign_t::ONES_COMPLEMENT:
+			case sign_t::TWOS_COMPLEMENT:
+				//complement only until end_bit
+				data_signal[0] = ((data_signal[0] ^ mask) & mask);
+				if(data_signal.size() > 1) {
+					for(int i=1; i < data_signal.size(); i++) {
+						data_signal[i] = data_signal[i] ^ 0xFF;
+					}
+				}
+				if(signal.get_sign() == sign_t::TWOS_COMPLEMENT)
+					data_signal[data_signal.size() - 1] = static_cast<uint8_t>(data_signal[data_signal.size() - 1] + 1);
+				break;
+			case sign_t::SIGN_BIT_EXTERN:
+				break;
+			default:
+				AFB_ERROR("Not a valid sign entry %d, considering the value as unsigned", signal.get_sign());
+				break;
+		}
+		return -1;
+	}
+	return 1;
+}
+
 /// @brief Parses the signal's bitfield from the given data and returns the raw
 /// value.
 ///
@@ -39,6 +99,14 @@ float decoder_t::parse_signal_bitfield(signal_t& signal, std::shared_ptr<message
 	uint8_t bit_size = (uint8_t) signal.get_bit_size();
 	uint32_t bit_position = signal.get_bit_position();
 
+	if(!signal.get_message()->frame_layout_is_little())
+	{
+		bit_position = converter_t::bit_position_swap(message->get_length(),
+							      signal.get_bit_position(),
+							      signal.get_bit_size());
+		message->frame_swap();
+	}
+
 	int new_start_byte = 0;
 	int new_end_byte = 0;
 	uint8_t new_start_bit = 0;
@@ -49,16 +117,12 @@ float decoder_t::parse_signal_bitfield(signal_t& signal, std::shared_ptr<message
 	for(int i=new_start_byte;i<=new_end_byte;i++)
 		data_signal.push_back(data[i]);
 
-//	if(bit_size > 255)
-//		AFB_ERROR("Error signal %s to long bit size",signal.get_name().c_str());
-
-//	if(new_start_bit > 255)
-//		AFB_ERROR("Too long signal offset %d", new_start_bit);
+	int sign = decoder_t::handle_sign(signal, data_signal, new_end_bit, data);
 
 	if(data_signal.size() > 65535)
-		AFB_ERROR("Too long data signal %s",signal.get_name().c_str());
+		AFB_ERROR("Too long data signal %s", signal.get_name().c_str());
 
-	return bitfield_parse_float(data_signal.data(), (uint16_t) data_signal.size(),
+	return static_cast<float>(sign) * bitfield_parse_float(data_signal.data(), (uint16_t) data_signal.size(),
 			new_start_bit, bit_size, signal.get_factor(),
 			signal.get_offset());
 }
@@ -84,8 +148,9 @@ openxc_DynamicField decoder_t::decode_bytes(signal_t& signal, std::shared_ptr<me
 	uint32_t length = message->get_length();
 	uint32_t bit_position = signal.get_bit_position();
 	uint32_t bit_size = signal.get_bit_size();
+
 	std::vector<uint8_t> new_data = std::vector<uint8_t>();
-	new_data.reserve(bit_size << 3);
+	new_data.reserve((bit_size / 8) + 1);
 
 	int new_start_byte = 0;
 	int new_end_byte = 0;
@@ -95,59 +160,29 @@ openxc_DynamicField decoder_t::decode_bytes(signal_t& signal, std::shared_ptr<me
 	converter_t::signal_to_bits_bytes(bit_position, bit_size, new_start_byte, new_end_byte, new_start_bit, new_end_bit);
 
 	if(new_end_byte >= length)
-	{
 		new_end_byte = length-1;
-	}
 
 	if(new_start_byte >= length)
 	{
-		AFB_ERROR("Error in description of signals");
+		AFB_ERROR("Error in signal's description");
 		return decoded_value;
 	}
 
-	uint8_t first = data[new_start_byte];
-	int mask_first = 0;
-	for(i=new_start_bit;i<8;i++)
-	{
-		mask_first = mask_first | (1 << i);
-	}
+	uint8_t mask_first_v = static_cast<uint8_t>(0xFF << new_start_bit);
+	uint8_t mask_last_v = static_cast<uint8_t>(0xFF >> (7 - new_end_bit));
 
-	uint8_t mask_first_v = 0;
-	if(mask_first > 255)
+	if(new_start_byte == new_end_byte)
 	{
-		AFB_ERROR("Error mask decode bytes");
+		data[new_start_byte] = data[new_start_byte] & (mask_first_v & mask_last_v);
 	}
 	else
 	{
-		mask_first_v = (uint8_t)mask_first;
+		data[new_start_byte] = data[new_start_byte] & mask_first_v;
+		data[new_end_byte] = data[new_end_byte] & mask_last_v;
 	}
 
-	data[new_start_byte]=first&mask_first_v;
-
-	uint8_t last = data[new_end_byte];
-	int mask_last = 0;
-	for(i=0;i<=new_end_bit;i++)
-	{
-		mask_last = mask_last | (1 << (7-i));
-	}
-
-	uint8_t mask_last_v = 0;
-	if(mask_last > 255)
-	{
-		AFB_ERROR("Error mask decode bytes");
-	}
-	else
-	{
-		mask_last_v = (uint8_t)mask_last;
-	}
-
-	data[new_end_byte]=last&mask_last_v;
-
-
-	for(i=new_start_byte;i<=new_end_byte;i++)
-	{
+	for(i=new_start_byte ; i <= new_end_byte ; i++)
 		new_data.push_back(data[i]);
-	}
 
 	decoded_value = build_DynamicField(new_data);
 
@@ -205,9 +240,8 @@ openxc_DynamicField decoder_t::decode_boolean(signal_t& signal, std::shared_ptr<
 
 	// Don't send if they is no changes
 	if ((signal.get_last_value() == value && !signal.get_send_same()) || !*send )
-	{
 		*send = false;
-	}
+
 	signal.set_last_value(value);
 
 
@@ -294,7 +328,6 @@ openxc_DynamicField decoder_t::decode_state(signal_t& signal, std::shared_ptr<me
 ///
 openxc_DynamicField decoder_t::translate_signal(signal_t& signal, std::shared_ptr<message_t> message, bool* send)
 {
-
 	// Must call the decoders every time, regardless of if we are going to
 	// decide to send the signal or not.
 	openxc_DynamicField decoded_value = decoder_t::decode_signal(signal,